I can't say enough how important it is to proofread carefully. Below are some funny "whoopsies" that I've seen:

1. I saw a sign in Richmond that read, "GOD LESS AMERICA." I think the "B" fell off.

2. When I was the marketing specialist for an engineering firm, my predecessor send out a multimillion dollar proposal to the "Department of Pubic Works." That missing "L" was crucial.

3. I saw a vanity plate on a cool Mustang. It read, "Mock 1." Somehow, I think he was going for "Mach."